Herpetological Conservation and Biology 14(3):601–614. Submitted: 1 May 2019; Accepted: 15 October 2019; Published: 16 December 2019. EVALUATING BEHAVIOR AND ENCLOSURE USE OF ZOO-HOUSED BROAD- SNOUTED CAIMAN (CAIMAN LATIROSTRIS): A CASE STUDY IN THE ZOO OF CÓRDOBA (ARGENTINA) LILEN PRYSTUPCZUK1,2, GERARDO C. LEYNAUD1,2, AND M. CARLA LABAQUE3,4,5 1Universidad Nacional de Córdoba, Facultad de Ciencias Exactas, Físicas, y Naturales, Centro de Zoología Aplicada. Rondeau 798, Córdoba (5000) Argentina 2Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Diversidad y EcologíaAnimal (IDEA), Rondeau 798, Córdoba, (5000) Argentina 3Universidad Nacional de Córdoba, Facultad de Ciencias Exactas, Físicas y Naturales, Catedra de Ecología, Avenida Vélez Sársfield 299 (X5000GCA), Córdoba, Argentina 4Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigaciones Biológicas y Tecnológicas (IIByT), Avenida Vélez Sársfield 1611 (X5016GCA), Córdoba, Argentina 5Corresponding author, email: [email protected] Abstract.—Zoo environments represent a useful opportunity for animal research, particularly for species that are difficult to observe in the wild. Moreover, studying the behavior of zoo-housed populations provides important information about the welfare state of animals. We described the behaviors of a zoo-housed population of seven Broad-snouted Caimans (Caiman latirostris) composed of males and females of different ages. We evaluated the associations of behavior frequencies with attributes of individuals (sex and age class) and with environmental variables (season, time of the day, and daily mean temperature). We calculated the Spread of Participation Index to estimate the use of space in relation to attributes of individuals and environmental variables. Additionally, we evaluated the suitability of the enclosure and management measures by assessing the Five Freedoms. The results showed higher frequencies of aquatic behaviors in adults than in subadults, which may reflect an ontogenetic shift in behavior or, conversely, may be a consequence of a dominance hierarchy. There were almost no differences in behavior frequencies between sexes. Aquatic behaviors were associated with lower temperatures, which could be attributed to thermoregulation. The results also showed daily movements from water in the morning to land at midday and in the afternoon. A high rate of agonistic behaviors was recorded, and possible causes and implications are discussed. Enclosure use was low, with some zones being poorly used or not used at all, and with marked variability among individuals. Finally, 53% of the husbandry recommendations for this species were met in the study population. Key Words.—captivity; crocodiles; ethogram; Five Freedoms; Spread of Participation Index Resumen.—Los zoológicos son ambientes que permiten avanzar en la investigación de diversas especies, particularmente aquellas difíciles de observar en vida silvestre. Los estudios de comportamiento en estos ambientes proveen información importante acerca del estado de bienestar de los animales. Aquí describimos los comportamientos de una población de siete Yacarés Overos (Caiman latirostris) compuesta por machos y hembras de distintas edades. Evaluamos la asociación de las frecuencias de comportamientos con atributos individuales (sexo y clase etaria) y con variables ambientales (temporada, hora del día y temperatura ambiente media). Calculamos el Índice de Dispersión de la Participación para estimar el uso del espacio en relación a atributos individuales y variables ambientales. Adicionalmente, evaluamos la adecuación del habitáculo y medidas de manejo mediante el análisis de las Cinco Libertades. Los resultados mostraron mayor frecuencia de comportamientos acuáticos en adultos que en subadultos, lo cual podría reflejar un cambio ontogenético comportamental o bien ser una consecuencia de la jerarquía de dominancia. Hubo pocas diferencias comportamentales entre sexos. Los comportamientos acuáticos estuvieron asociados a temperaturas bajas, pudiendo atribuirse al comportamiento de termorregulación. Los resultados también mostraron un movimiento diario desde el agua a la mañana hacia la tierra al mediodía y tarde. Registramos una alta tasa de comportamientos agonistas y se discutieron las posibles causas e implicancias. El uso del espacio fue reducido, con zonas escasamente utilizadas o no utilizadas, y marcada variabilidad entre individuos. Finalmente, un 53% de las recomendaciones de manejo para esta especie se cumplieron en la población en estudio. Palabras clave.—cautiverio; cocodrilos; etograma; Cinco Libertades; Índice de Dispersion de la Participación Copyright © 2019. Lilen Prystupczuk 601 All Rights Reserved. Prystupczuk et al.—Behavior and enclosure use of zoo-housed Broad-snouted Caimans. Bolivia, Brazil, Paraguay, and Uruguay (Verdade et al. 2010). The species has been threatened historically by hunting and habitat loss (Rueda-Almonacid et al. 2007). Several projects of sustainable use involving the ranching technique have been developed in Argentina, to contribute to the recovery of natural populations (Larriera and Imhof 2006). Broad-snouted Caimans that are illegally traded are confiscated and relocated to zoos, which function as reception centers (Aprile and Bertonatti 1996; Bertonatti 2017). Thus, in Argentina, captive populations of Broad-snouted Caiman are housed both in breeding farms and in zoos. The literature indicates that wild Broad-snouted Caimans limit their activities to basking and diving in winter, and that feeding, territorial fights, and copulation occur in spring and summer (Larriera and Imhof 2006). In captivity, FIGURE 1. Adult Broad-snouted Caiman (Caiman latirostris) at studies have focused on thermoregulatory (Verdade et Córdoba Zoo, Argentina. (Photographed by Lilen Prystupczuk). al. 1994; Bassetti et al. 2014;), agonistic (Verdade 1992, 1999), and reproductive behaviors (Verdade 1995; Piffer INTRODUCTION and Verdade 2002). The Córdoba Zoo, in Córdoba, Argentina (31°25’S; In captive animal husbandry, knowing the suitability 64°10’W), houses a population of Broad-snouted of the facilities and management measures is crucial Caimans of unknown life history that arrived at the to provide good standards of animal welfare (Broom zoo after separate confiscations from illegal traffic. 1991; Mellor 2016). In zoo-housed populations, the The goal of this study was to obtain a first estimation artificially created environment plays an important role of general indicators of the welfare of the population in determining the diversity of behaviors that animals and to provide the institution with guidelines for can display (Clark et al. 2012; Rose and Roffe 2013). its improvement. Thus, we aimed to describe the Enclosures that are suitable for a species stimulate the behavior and use of space of the Broad-snouted Caiman occurrence of appetitive behaviors (Duncan 1998), are population housed in the Córdoba Zoo, considering its enriching to the animals, and render a better quality associations with individual attributes (size and sex) experience for the visitors (Fabregas et al. 2012). Thus, and environmental variables (season, time of the day, animal behavior, as well as the way animals use the and temperature). We also assessed the adequacy of the available space, provides important information about enclosure, husbandry, and management measures in this the suitability of the enclosure of zoo-housed populations population according to the Five Freedoms (Appendix (Ross et al. 2011; Rose and Robert 2013). In recent Table), an internationally accepted guideline for animal years, an increasing number of studies on species of welfare (Farm Animal Welfare Council 1993). conservation and/or sustainable use interest have been conducted in zoos (Anderson et al. 2008; Fernandez and MATERIALS AND METHODS Timberlake 2008; Labaque et al. 2010, 2013; Loh et al. 2018). Zoo environments are particularly useful for the Animals and enclosure.—Our study involved seven study of species whose behaviors are difficult to observe Broad-snouted Caimans (three adult males, one adult in the wild. female, and three subadult females, according to the Crocodilians have a wide repertoire of behaviors, age classes proposed by Larriera et al. 2006) housed in including elaborate social and reproductive ones Córdoba Zoo. Their snout-vent length (SVL) and weight (Garrick and Lang 1977; Lang 1987; Senter 2008; Brien varied from 37–89 cm and 1.6–31.6 kg, respectively et al. 2013a). Given the close association between (Table 1). The enclosure consisted of a 130-m2 concrete climate and behavior demonstrated for reptiles (Brandt pool and a 90-m2 central island (Fig. 2). There were also and Mazzotti 1990; Seebacher 1999; Simoncini et 72 Hilaire’s Side-necked Turtles (Phrynops hilarii) in al. 2013), behaviors are expected to show daily and the enclosure, which we considered only in terms of the seasonal variations, as well as variations associated interspecific interaction with Broad-snouted Caiman. with sex and individual ontogenetic development Feeding consisted of chicken or beef, and live chicks (Hunt 1977; Morpurgo et al. 1993). The Broad- offered at the same time every day in spring and summer. snouted Caiman (Caiman latirostris; Fig. 1) is a South In fall and winter, feeding was interrupted, following the American crocodilian species occurring in Argentina, species physiology (Hutton 1987; Lance 2003). 602 Herpetological Conservation